I humbly suggest that if there is useful and correct alternative that alt=""
or alt=" " are not used but instead, back off from other uses. If the
information is descriptive or explanatory, alt="" be used as long as it does
not produce an ugly result in the rendering. I think also, we need to vear
away from the notion of a screen reader/AT concept here but instead, focus
on what the ultimate text would be. if the ultimate text would be a three
times string, it is a bad approach for everyone because it is redundant and
produces a heavier than necessary load.
----- Original Message -----
From: "Maciej Stachowiak" <mjs@apple.com>
To: "Steven Faulkner" <faulkner.steve@gmail.com>
Cc: <public-html@w3.org>; "W3C WAI-XTECH" <wai-xtech@w3.org>;
<wai-liaison@w3.org>; "Dan Connolly" <connolly@w3.org>; "Chris Wilson"
<Chris.Wilson@microsoft.com>; "Michael(tm) Smith" <mike@w3.org>
Sent: Sunday, May 11, 2008 7:12 PM
Subject: Re: HTML Action Item 54 - ...draft text for HTML 5 spec to require
producers/authors to include @alt on img elements.
Hi Steve,
On May 8, 2008, at 8:28 AM, Steven Faulkner wrote:
>
> Dear HTML WG members,
>
> The first draft of our rewrite of major sections of 3.12.2 "The img
> element" in the HTML5 draft is now available:
>
> http://www.paciellogroup.com/blog/misc/uc/
Thanks for writing up a proposal. This proposal does not cover the use
case where HTML generated by a tool does not have a textual
alternative available. Examples include:
- Dragging a photo into a WYSIWYG mail program's composer (Mail
programs do not normally prompt for a description and doing so would
be confusing to users)
- Bulk upload of photographs to a photo sharing site, where the
photographer is unwilling to put in the effort to individually
describe each one
- A script that scrapes images from other sources that lack text
alternatives, and generate html
These would all be covered by "Images of Pictures" but the required
description is not available. Thus, the proposal does not cover all
the use cases handled by the current spec language.
It also requires redundant text in many cases where the current spec
would call for empty alt. For example:
<p id="piedescription">According to a study covering several billion
pages, about 62% of documents on the Web in 2007 triggered the Quirks
rendering mode of Web browsers, about 30% triggered the Almost
Standards mode, and about 9% triggered the Standards mode.</p>
<p><img src="rendering-mode-pie-chart.png" alt="The majority of
documents triggered quirksmode." aria-describedby="piedescription"></p>
Is there any reason to believe that redundant text description of an
image that recapitulates the text is helpful, rather than harmful, to
users who use textual alternatives? After all, "The majority of
documents triggered quirksmode" is just a restatement of "62% of
documents on the Web in 2007 triggered the Quirks rendering mode of
Web browsers". Furthermore, aria-describedby would link the image to a
long description, thus possibly leading the screen reader user to hear
the same information yet a third time.
Is there reason to believe that screen reader users like to hear
things two or three times? I have not done any studies but this is
surprising to my intuition. I would have concluded that using alt=""
to present the screen reader user (or other users of aural or text-
only media) with the information only once is best. It may be that
this surprising conclusion is correct but I would like to hear some
justification.
Regards,
Maciej